Plastic Definition and 292 Threads

Hi all. I am now working on the uniaxial cold drawing on the plastic sheet (polybutylene succinate, a semicrystalline polymer). After uniaxial cold drawing, as expected, strength increased along the drawing direction/ machine direction (MD). Strength and elongation at break drastically...

Hi, does anyone know where to buy cheap plastic lenses online? I need lenses of 0.8-1.2mm diameter and 5-50mm F.L. Thanks

in the following question i am asked to find all the possible mechanisms, in the given state, and then when the "X" bar has an area of A and not 2A the answers are: when area of X=2A i) plastic hinge at D ii) yielding of Y and X bars iii) plastic hinge at C, yielding of "Y" bar...

http://www.stumbleupon.com/su/2RcIPs/blogs.discovermagazine.com/discoblog/2008/05/27/its-in-the-bag-teenager-wins-science-fair-solves-massive-environmental-problem/ Ok, interesting, but is this practical? Leaving aside the means by which you'd heat the mix to a cosy 37 degrees, what would be...

I discussed with my students that if force remains constant and mass decreases then acceleration increases (a=F/m). I also explained that if force remains constant and mass increases, acceleration decreases. I know that there are a number of variables that play into this next situation and I...

Homework Statement the graph below shows the behaviour of a sample of a metal when it is stretched until it starts to undergo plastic deformation. what is the total work done in stretching the sample from zero extension to 12.0mm? simplify calculation by treating the region xy as a...

the foollowing hollow shaft has a torsion applied to it so that the plastic area reaches the inner radius, what is the magnitude of the maximum residual shearing stress? http://lh3.ggpht.com/_H4Iz7SmBrbk/S9XK9ZwAbQI/AAAAAAAACFU/ueYSDTK5qMM/s800/Capture.JPG i don't see why there should...

My question is that would it be more environmentally friendly to burn plastics bags rather than letting them degrade? They take thousands of years to do so and even then many plastics do not completely break down beyond the molecular level...so instead of letting them hang around in the...

Homework Statement A sheet of plastic, n= 1.5, 25 mm thick is used in a bank teller's window. A ray of light strikes the sheet at an angle of 45 degrees. The ray leaves the sheet at 45 degrees, but at a different location. Use a ray diagram to find the distance between the ray that leaves and...

Homework Statement I have this lab and my goal is to find how far I should place a box if I was to catch a plastic leprechaun that weighs 22.4 grams fired out of an air cannon. I did this lab and the final velocity I ended with was 12.76 meters/sec (29.72 meters was the average distance and...

Homework Statement The figure shows a positively charged plastic rod of length L = 2.40 m and uniform linear charge density 8.00×10-3 C/m. Setting V= 0 at infinity, find the electric potential at point P for d = 1.536 m. Homework Equations The Attempt at a Solution Alright, I...

Looking for a flexible plastic, equivalent to TPE shore A 50-60. Finish to be similar to ABS or PC, which mean high gloss, polish finish; that can be injection molded. Can somebody recommend a plastic resin that meet those criteria? -robert

Homework Statement Your physics assignment is to figure out a way to use electricity to launch a small 6.0-cm-long plastic drink stirrer. You decide that you'll charge the little plastic rod by rubbing it with fur, then hold it near a long, charged wire. When you let go, the electric force...

Hello there, I am having difficulty with this question: A 0.2 kg plastic cart (Cart a) and a 20 kg (Cart b) lead cart can both roll without friction on a horizontal surface. Equal forces are used to push the two carts forward for a distance of 1 m, starting from rest. Which cart has the...

Homework Statement In figure (a) below, an electron is shot directly away from a uniformly charged plastic sheet, at speed vs = 2.13 × 10^5 m/s. The sheet is nonconducting, flat, and very large. Figure (b) below gives the electron's vertical velocity component v versus time t until the return...

Homework Statement The index of refraction for blue light in plastic is 1.46 and for red light is 1.39. Determine the angular spread of the spectrum leaving the plastic block [presumably to air] for a beam of white light incident at angle of 45° to the plastic block.Homework Equations...

Young's Modulus for Plastic URGENT I was wondering what is the young's modulus for plastics because I am looking all over the internet and can't find anything? Its because in an experiment i calculated it to be 10.9GPa but i need to compare it to an actual value. Thanks

What causes water and other similar transparent things to become transparent? Visible light can pass through transparent solid object like glass but can't pass through many opaque objects. What is the reason? Again when liquid water turns into ice it loses its transparency. I'll be very...

As the title suggests, i have to make cuts in a piece of plastic about the same dimensions as a credit card. the shapes themselves are fairly simple, mostly triangles, with 4 quarter circles on the corners. the device i have in mind would be something which i guess looks like a mechanical...

So, students are supposed to write their name on the plastic name plaque using vis a vis markers. After the class, it should be a simple matter to wipe the names off with a paper towel and water. Except that, somehow, a Sharpie from the last class is placed in the vis a vis can and one of...

Hey all, I'm trying to make a cylindrical bonded magnet, but I need to compress it in a non magnetizable pipe capable up withstanding up to 10000 psi pressure, 1 cm or less in diameter. PVC only has a tensile rating of 7500 psi so it won't do. i would like to know what plastic(or any non...

Hi all. Is there anbetter way to Mold the Tip of a plastic tube, other than Glass-molding? I got a plastic tube, about 350cm long, 1.6mm OD, and 0.9mm ID (hence thickness = .35mm). Its a hollow tube (Duh!), and i need to mold , or rather form the end of this tip, into a more conical...

I've noticed that plastic cups exhibit some interesting physical behavior. Some paper cups(maybe all actually, I'm not sure) have concave bottoms, and when the liquid in the cup gets high enough, the forces from simply raising the beverage from the table to my mouth create enough force to pop...

Help me!A spinning blue plastic object made me sleepless. I've seen the mit online vedio course Physics I: Classical Mechanics Lecture 21 Torques, Oscillating Bodies,near the end 44:19.There is a spinning blue plastic object,the teacher spun it, it revolved then it stoped,then it revolved...

If the water stays in a plastic bottle for a while, I can taste the plastic in it. Plastic flavor. The taste is as it smells. Have any of you ever noticed this? Am I actually drinking plastic? I don't find this taste in glasses or ceramic or metal. But it's definitely in the plastic and it's...

Hello, I need some help with the general very basic cost analysis of an injection molding machine and a mold for a particular part (Plastic Gear). For example, a Gear made out of Nylon plastic resin. The gear dimensions are roughly 2 cm diameter (20 teeth). Something like the black one...

hI! I'm trying to understand here a little bit of plastic analyses,but i can understand in the page of the book bellow,why the work at the plastic hinge is equal to MPx2theta?why MP and not MA? can someone explain me this with some angle relation or trigonometrics? the second is why the...

Is there any research done on plastic engine blocks or cannon barrels ? I interested in using plastics at high heat high pressure environments after learning some researchers cools 1600 degree plate to 80 degrees with potassium or sodium or exotic metallic liquids. I think it might be possible...

I am trying to predict elastic wheel deformation. I am not quite sure how to do it. How might one approach the problem? Take a steel wheel: 6 in. diameter, 2 in. thick, with a contact force of 1000lbs E = 30,000,000 psi Poisson ratio: .27 Would one calculate this in finite layers...

On my mouse cable, there is a blob of plastic which coils the wire once around, I don't know what the material is that encompasses it. Someone said it was for to stop UHF flashback. What does this mean? I also have it on loads of electrical appliances.. Cheers Philip

Hi Guys, Can anybody advise me where to get chart for tolerance class of 11e28 and 10e28 for the plastic Gears?

Homework Statement Three plastic sheets that are large, parallel and uniformly charged are placed side-by-side. The electric field strength between sheets 1 and 2 is 2x105; the electric field strength between sheets 2 and 3 is 6x105. What is the ratio of the charge density on sheet 3 to that on...

PVC, PEC or ?? I am looking for some help in determining the appropriate type of plastic for my application. I am in the process of having a slide chart manufactured out of plastic. It was recommended that I use 0.024 inch thick clear PVC. The samples produced with the PVC were fine with...

Hi all, Homework Statement I'm stupefied. In continuation to my last thread (https://www.physicsforums.com/showthread.php?t=277124), I wanted to see if any perfectly plastic collision would make the total mechanical energy of the system go down to a factor of \frac{1}{\sqrt 6}. I got a...

Homework Statement Today a friend of mine came to my apartment and we discussed a problem. I realized something that surprises me A LOT. Consider the following situation. There are 2 disks of radius R and mass M on a frictionless table. One doesn't move while the other suffers a translation...

2 balls, with masses of M1, M2, are involved in a plastic collision, one dimentional.. the kinetic energy of the ball m1 is 20 times that of m2. at what ratio between the masses will the new mass(m1+m2) move in the direction the lesser energy mass mas moving. it seems to me that there is too...

A plastic rod has been bent into a circle of radius R=8.20cm. It has a charge Q1 = +4.20pC uniformly distributed along one-quarter of its circumference and a charge Q2 = -6Q1 uniformly distributed along the rest of circumference. With V=0 at infinity, what is the electric potential a) at the...

Hello, I'm a bit confused here about this topic. I can't seem to find a proper book on it so reading loads of papers of try and get a grip on it. I had come to the understanding that the high tensile and yeild strength developed here was due to the subgrain/micrograin size and the partial...

Is it alright to reuse plastic water bottles or leave them out in the sun or heat before using them? My dear mother seems to think that it isn't alright but I am not sure why. Is there a more reliable source that answers this question than a first link off google...

Hello: Can someone help with this? A long, thin, nonconducting plastic rod is bent into a circular loop that has radius a. Between the ends of the rod a short gap of length l, where l << a remains. A positive test charge of magnitude Q is evenly distributed on the loop. What's the...

Hi, I want to learn that do atoms or crystals dislocate in the plastic deformation of metals.

i have been taught that plastic bags damage the environment because they take thousands of years to decompose. this is not an explanation though. why is it bad that they take ages to decompose? i guess animals get trapped in them and some plastics are toxic but it would seem easy to put the...

Take a look at this slide show: http://www.poconorecord.com/_flash/soundslides/20080505plasticbags/soundslider.swf "There's harsh economics behind There's harsh economics behind bag recycling: It costs $4,000 to bag recycling: It costs $4,000 to process and recycle 1 ton of plastic...

Hi everyone, I'm having a bit of difficulty interperting the results of an ANSYS model I'm currently running. This is of a small, thin piece of metal (0.018" in thickness, ~1"x1" length x width), that I am fixing at one end and displacing the other end ~0.015". Essentially this is a...

Hi Is there anyone, that can explan why the melting and crystallization peak of a plastic don not have same position in DSC scan?

Hello all, As the father of an infant son and an avid user of plastic bottles, the news from Canada and the US concerning the safety of certain plastic containers for children (and adults) made me investigate what types of bottles are safe. A quote from the Today Show: Is that...

Hello, What is Plastic Engineering? What Engineering major as a BS is similar to Plastic? I am thinking it would probably be Nuclear? I am just curious what Plastic Engr is. Thank you in advance.. Take care,

Homework Statement Your physics assignment is to figure out a way to use electricity to launch a small 6.0-cm-long plastic drink stirrer. You decide that you'll charge the little plastic rod by rubbing it with fur, then hold it near a long, charged wire. When you let go, the electric force...

I was drinking from a plastic cup today with some physics friends, and we noticed that when we bent the cup, a white patch of plastic would form there, and the plastic would not be transparent at that point anymore. We were baffled by this observation, and none of us could really explain what...

How do the magnetic stripe readers in credit/debit equipment work? I am more curious how placing the credit card inside a plastic bag then swiping it works? I see it all of the time out in the field and I don't understand it.